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HETG Spectral-imaging of SN1987A

HETG Spectral-imaging of SN1987A. Dan Dewey, MIT Kavli Inst. with Svet Zhekov (SRI Sophia & U Colorado), C.R. Canizares (MKI), R. McCray (U Colorado) Eight Years of Science with Chandra, 23 October 2007. Overview. Introduction to SN 1987A HETG Observations & Spectral results

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HETG Spectral-imaging of SN1987A

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  1. HETG Spectral-imaging of SN1987A Dan Dewey, MIT Kavli Inst. with Svet Zhekov (SRI Sophia & U Colorado), C.R. Canizares (MKI), R. McCray (U Colorado) Eight Years of Science with Chandra, 23 October 2007

  2. Overview • Introduction to SN 1987A • HETG Observations & Spectral results • Spectral images: Modeling and velocities • Future of SN 1987A HETG SN1987A - 8 Years of Science with Chandra

  3. Introduction to SN 1987A • Proceedings of Aspen conference:"Supernova 1987A: 20 Years After: Supernovae and Gamma-Ray Bursters" AIP, New York, eds. S. Immler, K.W. Weiler, and R. McCray • Presentations on-line at:http://astrophysics.gsfc.nasa.gov/conferences/supernova1987a/ HETG SN1987A - 8 Years of Science with Chandra

  4. HST imaga and model From ESA/Hubble: http://www.spacetelescope.org/news/html/heic0704.html HETG SN1987A - 8 Years of Science with Chandra

  5. CSM frombinary history • Morris andPodsiadlowski2007. • Creation of thetriple-ring system. 2D cylindrical sliceat time of SN explosion HETG SN1987A - 8 Years of Science with Chandra

  6. Shocks and Regions FromPun et al. 2002 HETG SN1987A - 8 Years of Science with Chandra

  7. Out-of-Planestructure • Large, equatorialHII region swept-up by blast wave. • Other structuresalong polar axis? From Gaensler, Aspen'07 (based on Michael et al. 2003) HETG SN1987A - 8 Years of Science with Chandra

  8. -- Recent HETG Obs.s -- • 360 ks of GTO time (Canizares PI) 2 keV 1 keV 0.65 keV MEG minus plus HEG minus plus 2 Å 20 Å HETG SN1987A - 8 Years of Science with Chandra

  9. Chandra & SN 19897A • HETG (1999.8), Garmire/GTO - Michael et al.(2002) • ACIS (2 per year), Burrows, Park et al. • LETG (2004.7), McCray, Zhekov et al. • HETG (2007.23), Canizares/GTO <--- • LETG (2007.7), McCray • HRC-I (~ 2008.3), Murray/GTO HETG SN1987A - 8 Years of Science with Chandra

  10. HETG spectra of '87A Plus orders, Minus orders MEG HEG HETG SN1987A - 8 Years of Science with Chandra

  11. 2-vpshock fit to data • Good fit w/NEIVERS 2.0, Borkowski APEC • Possible broad excess ? HETG SN1987A - 8 Years of Science with Chandra

  12. Summary of spectral results • Flux increase ~ 20% per 6 months • Consistent with ACIS monitoring (Park) • "Shock DEM": distribution 0.3 - 3 keV • Abund.s, NH: similar to Zhekov 2006. • 2 shock approx.: 0.55 and 2.11 keV • Line centers: consistent with 286 km/s • Broad component (?) ~ 9000 km/s. HETG SN1987A - 8 Years of Science with Chandra

  13. SN 1987A is resolved • Tilted, thin ring models the zeroth-order • Intensity varies with ring azimuth The DATA Model Model w/PSF 1.7" diameter ring HETG SN1987A - 8 Years of Science with Chandra

  14. ~ 600 events Spectral images,FWHM in orders Ne X, ~ 1 keV MEG minus MEG plus HETG SN1987A - 8 Years of Science with Chandra

  15. Ring Doppler effect Blue shifted From the Chandra POG Red shifted HETG SN1987A - 8 Years of Science with Chandra

  16. http://space.mit.edu/hydra/sources.html Fitting 1D projections Model Data HETG SN1987A - 8 Years of Science with Chandra

  17. V_Ring for the lines • Continuousdistribution ? • Discretevelocitiesby component ? HETG SN1987A - 8 Years of Science with Chandra

  18. Modeling the Spectral-Images • Simple tilted ring • Azimuthal intensity variation • Two spectral components 2.11 & 0.55 keV • Ring velocity foreach component,470 km/s and 240 km/s • … and … HETG SN1987A - 8 Years of Science with Chandra

  19. Adding "V_Turbulence" • Additional velocity blur of 200 km/s RMS No blur: "blue" excess With blur: better fit Model Residual Residual Model The DATA HETG SN1987A - 8 Years of Science with Chandra

  20. Interpreting the additional blur • Turbulent velocity • Ion thermal velocity • Oblique shocksgive range of directions.Smith & McCray 2007 HETG SN1987A - 8 Years of Science with Chandra

  21. Shock Temp and Velocities • Strong, adiabatic shock model has: V_bulk ~ 3/4 V_shock • Post-shock temp and shock velocity: kTe ~ 1.4 keV (V_shock/1000 km/s)2 • kTe ~ 0.55 keV ---> V_bulk ~ 470 km/s • kTe ~ 2.11 keV ---> V_bulk ~ 920 km/s • In reality, complexity reduces V_bulk ? HETG SN1987A - 8 Years of Science with Chandra

  22. Summary of Spectral-Imaging • Bulk radial motion of X-ray emitting plasma is ~ 200 -- 600 km/s. • Additional "turbulent" velocity range of~ 200 km/s RMS is indicated. • No need for emission out-of-the-equatorial-plane, beyond +/- 25 deg. • Broad component (?) with FWHM~ 9000 km/s -- geometry undetermined. HETG SN1987A - 8 Years of Science with Chandra

  23. Future Missions and '87A… • Three words: Chandra, Chandra, Chandra • What future Instrument do you want ? • "What are you rebelling against?""What have ya got?"--> Better instruments are always welcome. • Long-slit [X-ray] GratingSpectrometers are veryuseful (FUSE, STIS, IRS.) HETG SN1987A - 8 Years of Science with Chandra

  24. SN 1987A in the future • Blastwave continues,reaching Outer Rings • Other CSMinteractions • Detailed CSM knowledge, Sugerman et al. 2005 • "To astrophysicists in the year 2987." -E. Michael, thesis dedication. 7 arc seconds HETG SN1987A - 8 Years of Science with Chandra

  25. The End • Thank you HETG SN1987A - 8 Years of Science with Chandra

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